“Horn OK Please,” in one form or another, is written prominently on the back of almost every truck—large or small—in Mumbai. The signs intrigued me. Why is the horn okay? What’s the point of the invitation? Mumbai is a constant cacophony of honking without additional encouragement—or maybe because of it.

What I learned, finally, after years of silent, befuddled amusement, is that “horn ok please” actually means “please do not use your horn.”

You know: yes means no.

Even the chicken truck says “Horn OK Please.” Only the free mortuary van lacks the sign, due to its protruding casket.